System and method for measuring radiation characteristic of antenna

ABSTRACT

An antenna measurement system is provided to measure the radiation characteristic of a source antenna ( 2 ), and obtain more correct far-field range data within a short period of time. The antenna measurement system includes a tester body placed apart from the source antenna ( 2 ) with a predetermined distance. A plurality of measurement modules ( 20 ) are arranged at the tester body in a predetermined pattern. Each measurement module has an IC chip ( 22 ) for processing positional information and measured values to generate relevant signals, and a tester antenna for receiving and transmitting the signals from the IC chip ( 22 ). Upon receipt of frequency signals from the source antenna ( 2 ), the tester antenna ( 24 ) generates induced power for driving the IC chip ( 22 ), and transmits the measured values for the frequency signals to the IC chip ( 22 ). A measurement controller ( 30 ) receives the signals from the tester antenna ( 24 ), and data-processes the positional information and the measured values of the respective measurement modules ( 20 ).

This application is a 371 of PCT/KR03/02788 filed on Dec. 19, 2003.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a system and a method for measuring theradiation characteristic of an antenna, and more particularly, to anantenna measurement system and an antenna measurement method whichspeedily measure the radiation characteristic of a source antenna usingmicro-scaled test antennas and IC chips.

(b) Description of the Related Art

Generally, among the antenna ranges which are used to measure theradiation characteristic (the phase, or the intensity or amplitude) ofthe antenna, are there a far-field range where the measurement is madewhile the source antenna is placed far from the tester or receiverantenna, a near-field range where the measurement is made by using thesource antenna as a transmitter and taking samples near to sourceantenna with a probe per a predetermined distance, and a compact rangewhere the measurement is made while the source antenna is placed near toa reflector antenna being the tester antenna.

The far-field range is further classified into an elevated range wherethe measurement is made while the source antenna and the tester antennaare installed at a tower, a building or the top of a hill, a slant rangewhere the measurement is made while one of the source and the testerantennas is placed at high position and the other on the ground, and ananechoic chamber where the measurement is made in a room having a wallwith absorbents for removing the possible reflection. The elevated rangeand the slant range involve lower cost for the installation andmeasurement of the relevant elements, but practically require very widearea and high tower, with the disadvantage of being much influenced bythe external weather. The anechoic chamber involves the indoormeasurement, and is not influenced by the external weather, with thedisadvantage in that much cost is needed to make a large laboratory (forexample, making it with a vertical length of 10 m, a horizontal lengthof 10 m and a height of 5 m) with absorbents.

The far-field distance r_(ff) between the source antenna and the testerantenna is given by r_(ff)=2D²/λ (where D indicates the inter-distanceof the source antenna, and λ indicates the operation frequency). Asillustrated with the 70 m reflector antenna operated at 2.3 GHz, thefar-field distance r_(ff) is determined to be 75 km. Accordingly, withthe case of the elevated range or the slant range, the distance betweenthe source and the tester antennas becomes enlarged. As various objectssuch as trees, forests, hills, rivers and buildings are existent betweenthe source antenna and the tester antenna, it is very difficult to makethe correct measurement, and to quickly cope with the variablemeasurement situations. Consequently, the measurement values are largelydifferentiated due to the difference in the temperature, and theweather. Moreover, with the case of the far-field range, the sourceantenna is exposed to the outside to obtain the correct measured values,and hence, it becomes difficult in the radar or military antennas tomake the desired measurement while keeping a secret.

The compact range is desirably installed within the relatively smallspace, but it undesirably requires a large-scaled reflector.

With the compact range, the measurement may be made in a very smallspace provided that the inter-distance of minimally 1 wavelength is madeto the source antenna. However, as the probe should precisely move inthe X and Y axial directions to correctly figure a predetermined plane(the plane perpendicular to the central axis of the source antenna)within the short distance, much time and cost are consumed to make theequipment for moving the probe (the tester antenna), and to make thedesired measurement.

The anechoic chamber also involves the same problem as with thenear-field range in that the measurement is made using a probe.

That is, with the case of the near-field range and the anechoic chamber,as the data measured at the probe are all transformed into far-fieldrange data, the correct data can be obtained only when the probe movesvery precisely. The precision in the movement of the probe is severalmicrometers to several tens micrometers. As the carrier for moving theprobe very precisely is made with a high cost of up to hundreds ofmillions, it is practically difficult with the small-scale companies tomake measurement experiments related to the development of antennas in asufficient manner.

As the measurement is made while moving the probe in a slight manner,several hours are consumed even to make the measurement once, and thismeans that considerable time is wholly needed to complete the requiredmeasurements. Furthermore, with the high possibility of making errors inthe measuring due to the variable environmental conditions, it becomesimpossible to make the total inspection with respect to the producedantennas, and only the deficient sampling test can be made.

In order to obtain more correct far-field range data, it is required toenlarge the mobile range (the plane area) of the probe, but such anenlargement is practically limited due to the carrier for moving theprobe.

Furthermore, the carrier for moving the probe is liable to generateelectromagnetic waves, which are applied to the measured values asnoises.

Furthermore, with the case of the near-field range and the anechoicchamber, as the measurement is made only to the front side of the sourceantenna, it is impossible to make correct expressions for the back lobe.In order to correctly express the back lobe, it is necessary todirectionally reverse the source antenna and make the measurement again,and this involves the long measurement time increased by two times.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an antennameasurement system which can quickly and precisely measure the radiationcharacteristic of a source antenna (the phase, or the intensity oramplitude) using micro tester antennas and IC chips, thereby obtainingcorrect far-field range data.

It is another object of the present invention to provide an antennameasurement method which measures the radiation characteristic of asource antenna (the phase, or the intensity or amplitude) by arranging aplurality of measurement modules at a plane or sphere-shaped tester bodyeach with a micro tester antenna and an IC chip, thereby obtainingcorrect far-field range data within a short period of time.

According to one aspect of the present invention, the antennameasurement system includes a tester body placed apart from the sourceantenna with a predetermined distance. A plurality of measurementmodules are arranged at the tester body in a predetermined pattern. Eachmeasurement module has an IC chip for processing positional informationand measured values to generate relevant signals, and a tester antennafor receiving and transmitting the signals from the IC chip. Uponreceipt of frequency signals from the source antenna, the tester antennagenerates induced power for driving the IC chip, and transmits themeasured values for the frequency signals to the IC chip. A measurementcontroller receives the signals from the tester antenna, and processesthe positional information and the measured values of the respectivemeasurement modules.

According to another aspect of the present invention, in a method ofmeasuring the radiation characteristic of a source antenna, a pluralityof measurement modules are arranged at a tester body in a predeterminedpattern. Each module has an IC chip for processing positionalinformation and measured values to generate signals, and a testerantenna for receiving and transmitting the signals from the IC chip.Upon receipt of frequency signals from the source antenna, the testerantenna generates induced power for driving the IC chip, and transmitsthe measured values for the frequency signals to the IC chip. The testerbody is placed apart from the source antenna with a predetermineddistance such that the tester body is perpendicular to the central axisof the source antenna. With the operating of the source antenna, themeasurement controller is operated such that it receives anddata-processes the positional information and the measured values fromthe tester antenna of each measurement module provided at the testerbody.

According to still another aspect of the present invention, in a methodof measuring the radiation characteristic of a source antenna, aplurality of measurement modules are arranged at a tester body in apredetermined pattern. Each module has an IC chip for processingpositional information and measured values to generate signals, and atester antenna for receiving and transmitting the signals from the ICchip. Upon receipt of frequency signals from the source antenna, thetester antenna generates induced power for driving the IC chip, andtransmits the measured values for the frequency signals to the IC chip.The source antenna is placed within the tester body such that it ispositioned at the center of the tester body. With the operating of thesource antenna, the measurement controller is operated such that itreceives and data-processes the positional information and the measuredvalues from the tester antenna of each measurement module provided atthe tester body.

The tester body is shaped with a plane, a circular arc, a sphere, asemi-sphere, a hexahedron, a hexahedron with no bottom side, a cone, aquadrangular pyramid, an octahedron, a dodecahedron, an icosahedron, ora horn.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention, and many of the attendantadvantages thereof, will be readily apparent as the same becomes betterunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings in which likereference symbols indicate the same or the similar components, wherein:

FIG. 1 is a schematic perspective view of an antenna measurement systemaccording to a first embodiment of the present invention;

FIG. 2 is a plan view of a measurement module for the antennameasurement system shown in FIG. 1;

FIG. 3 schematically illustrates a tester antenna for the antennameasurement system shown in FIG. 1;

FIG. 4 schematically illustrates a first variation of the tester antennashown in FIG. 3;

FIG. 5 schematically illustrates a second variation of the testerantenna shown in FIG. 3;

FIG. 6 schematically illustrates a third variation of the tester antennashown in FIG. 3;

FIG. 7 schematically illustrates a fourth variation of the testerantenna shown in FIG. 3 in an exploded manner;

FIG. 8 illustrates the bottom side of the tester antenna shown in FIG.7;

FIG. 9 is a graph illustrating the radiation pattern of the E-planemeasured using the tester antenna shown in FIG. 4;

FIG. 10 illustrates the state of the tester antenna measuring the x-yplane in the radiation pattern shown in FIG. 9;

FIG. 11 illustrates the state of the tester antenna measuring the z-yplane in the radiation pattern shown in FIG. 9;

FIG. 12 illustrates the state of the tester antenna measuring the z-xplane in the radiation pattern shown in FIG. 9;

FIG. 13 is a block diagram illustrating the operation of the testerantenna and the IC chip;

FIG. 14 is a partial sectional perspective view of an antennameasurement system according to a second embodiment of the presentinvention;

FIG. 15 is a partial sectional perspective view of an antennameasurement system according to a third embodiment of the presentinvention;

FIG. 16 illustrates the antenna measurement system shown in FIG. 15where the tester body is in a standing state;

FIG. 17 is a partial sectional perspective view of an antennameasurement system according to a fourth embodiment of the presentinvention; and

FIG. 18 is a partial sectional perspective view of an antennameasurement system according to a fifth embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of this invention will be explained with referenceto the accompanying drawings.

FIG. 1 is a schematic perspective view of an antenna measurement systemaccording to a first embodiment of the present invention, and FIG. 2 isa plan view of a measurement module for the antenna measurement systemshown in FIG. 1.

As shown in FIGS. 1 and 2, the antenna measurement system includes atester body 10 placed distant from a source antenna 2 by a predetermineddistance, a plurality of measurement modules 20 arranged at the testerbody 10 in a predetermined pattern, and a measurement controller 30.Each measurement module 20 has an IC chip 22 for processing thepositional information and the measured values to generate the relevantsignals, and a tester antenna 24 for receiving and transmitting thesignals from the IC chip 22. Upon receipt of the frequency signals fromthe source antenna 2, the tester antenna 24 generates induced power fordriving the IC chip 22, and transmits the measured values for thefrequency signals to the IC chip 22. The measurement controller 30receives the signals from the tester antennas 24 of the measurementmodules 20, and processes the positional information and the measuredvalues of the respective measurement modules 20.

A receiver antenna 32 is installed at the measurement controller 30 toreceive the signals from the tester antenna 24. With the measurementcontroller 30, a built-in software makes transformation of the measuredvalues into far-field range data.

The tester body 10 is formed with a plane shape using a material littledispersed or reflected against the frequency signals from the sourceantenna 2.

As shown in FIG. 2, the measurement module 20 has a substrate 21 shapedwith a rectangle, a circle or an oval having a length or a maximumdiameter of 2-4 mm. The IC chip 22 and the antenna 24 are mounted on thesubstrate 21 by a surface mounting technique.

Alternatively, the IC chip 22 and/or the antenna 24 may be directlyformed on the substrate 21 by printing or photolithography.

The IC chip stores the number peculiar to its location. It is possibleto use a coordination value as the characteristic number for thelocation stored at the IC chip 22. For instance, with the measurementmodules 20 arranged at the first row, the characteristic numbers areassigned thereto in the sequence of (X1, Y1), (X2, Y1), . . . , (Xm,Y1). With the measurement modules 20 arranged at the last row, thecharacteristic numbers are assigned thereto in the sequence of (X1, Yn),(X2, Yn), . . . , (Xm, Yn).

The IC chip 22 is programmed such that it transforms the values receivedat the tester antenna 24 related to the phase and the amplitude of thefrequency signals or the dimension of the induced power into digitalsignals, and transmits them via the tester antenna 24.

As the IC chip 22 is currently made with several micrometers, it can bemounted on the substrate 21 with the micrometer-leveled size.

An amplification circuit is preferably installed at the IC chip 22 toamplify the micro-scaled frequency signal or induced power, and obtainprecise measurement results.

The IC chip 22 is programmed such that it combines the measured valuefrom the tester antenna 24 with the characteristic numbers in apredetermined sequence to generate a predetermined measurement signal,and transmits it via the tester antenna 24 together with the triggersignal.

The tester antenna 24 has a micro-scaled size such that it can bemounted on the substrate 21 with a very small size. A microstrip patchantenna or a dielectric chip antenna can be used as the micro testerantenna with a size of several millimeters.

Furthermore, the tester antenna 24 may have an ultra-micro size suchthat it can be mounted on the substrate 21 with a micrometer size.

As the size of the tester antenna 24 is increased, the measurementmodule 20 becomes enlarged. In this case, it is impossible to make themeasurement per a minute distance, and accordingly, a correctmeasurement value cannot be obtained with the transformation of themeasured values into far-field range data. Furthermore, in case thetester antenna 24 has a large size, it is likely that an error may bemade in the measured values due to the impedance variation by theinter-coupling of the neighboring antennas. Therefore, in order toobtain the correct measured values, it is necessary to minimize thetester antenna 24.

However, with the conventional dipole antenna, micro-strip patch antennaand dielectric chip antenna, it is impossible to make the antenna with asize of 2 mm or less.

In this respect, a new micro-scaled antenna structure is presented withthe inventive system.

That is, the tester antenna 24 has wires spirally wound on two ormore-leveled imagined planes, respectively. The wires formed at theimagined plane neighbors are connected to each other at their centralends or peripheral ends to form a single line.

As shown in FIG. 3, the antenna 24 has wires 42, 44 and 46 spirallywound on first to third imagined planes. In order to form a single line,the wires 42 and 44 formed at the first and second imagined planes areconnected to each other at their central ends using an interconnectionline 43. The wires 44 and 46 formed at the second and third imaginedplanes are connected to each other at their peripheral ends using aninterconnection line 45.

A feeder 48 is connected to the peripheral end of the wire 42 formed atthe bottommost first imagined plane.

If the wires 42, 44 and 46 and the interconnection lines 43 and 45 areelongated by holding the peripheral end of the wire 46 and the feeder48, the whole wire portions make formation of a single line.

The wires 42, 44 and 46 may be outlined with various shapes, such as arectangle, a circle, an oval, a hexagon, or an octagon.

It is preferable to shorten the length of the interconnection lines 43and 45 as much as possible.

When the length of the interconnection lines 43 and 45 becomes smaller,the distance between the neighboring wires 42, 44 and 45 is narrowed sothat the inter-impedance thereof is maximized to thereby compensate forthe increased capacitance.

Furthermore, it is preferable to form an insulating layer (not shown)between the wires 42, 44 and 46 to prevent the possibleshort-circuiting.

Alternatively, as shown in FIG. 4, the tester antenna 24 may have wires52 and 54 spirally wound on the two-leveled imagined planes,respectively. The wires 52 and 54 are connected to each other at theirperipheral ends using an interconnection line 55. A feeder 58 isconnected to the central end of the wire 52 formed at the lower imaginedplane.

FIG. 9 illustrates the radiation pattern of the E-plane measured at 390MHz while the tester antennas 24 are arranged in various directions asillustrated in FIGS. 10 to 12.

The radiation pattern is measured by establishing the distance betweenthe transmitter side of the tester antenna and the receiver side thereofto be 122 cm, and the heights thereof identically to be 204 cm. Thetester antenna 24 is structured such that the horizontal length of theoutermost spiral portion thereof is established to be λ/86.2 mm of thewavelength (λ), and the vertical length thereof to be λ/57.1 mm. Theantenna portions are wound four times with the same distance, and theheight of the two imagined planes is established to be λ/285.7 mm.

Compared to the conventional dipole antenna, the x-y plane of FIG. 9 wasmeasured by installing the tester antenna 24 to be in the stateillustrated in FIG. 10. The z-y plane was measured by installing thetester antenna 24 to be in the state illustrated in FIG. 11. The z-xplane was measured by installing the tester antenna 24 in the stateillustrated in FIG. 12.

As shown in FIG. 9, the three cases all exhibited a radiation patternsimilar to that of the dipole antenna.

Furthermore, as shown in FIG. 5, the tester antenna 24 may have fivewires 62, 64, 66, 67 and 69 spirally wound on the five-leveled imaginedplanes. The wires 62 and 64 formed at the first and second imaginedplane neighbors as well as the wires 66 and 67 formed at the third andfourth imagined plane neighbors are connected to each other at theirperipheral ends using interconnection lines 63. The wires 64 and 66formed at the second and third imagined plane neighbors as well as thewires 67 and 69 formed at the fourth and fifth imagined plane neighborsare connected to each other at their central ends using interconnectionlines 65. A feeder 68 is connected to the central end of the wire 62formed at the bottommost imagined plane.

As described above, the tester antenna 24 is structured such that thewires formed at the imagined plane neighbors are connected to each otherrepeatedly at their central ends and at their peripheral ends in analternate manner while wholly forming a single line.

As shown in FIG. 6, the tester antenna 24 may be structured such thatthe wires 72, 74 and 76 formed at the imagined planes are spirally woundeach in the shape of an oval, and connected to each other usinginterconnection lines 73 and 75 while forming a single line. A feeder 78is connected to the bottommost wire 72.

As shown in FIGS. 7 and 8, the antenna 24 may be structured such thatfour dielectric films 80 are placed at first to fourth imagined planes,and spiral wires 82, 84, 86 and 87 are printed on the one-sided surfacesthereof. Through holes 83 are formed at the first and third-leveleddielectric thin films 80 such that they are connected to the centralends of the wires 82 and 86. Through holes 85 are formed at the secondand fourth-leveled dielectric thin films such that they are connected tothe peripheral ends of the wires 84 and 87. The through holes 83 and 85are filled with conductive powder, and the four dielectric thin filmsare closely adhered to each other to form a single chip. The chip isheated at a predetermined temperature, and the conductive powder in thethrough holes 83 and 85 are molten so that the wire neighbors areconnected to each other to form a single line.

As described above, the dielectric thin film where the through hole isconnected to the central end of the wire, and the dielectric thin filmwhere the through hole is connected to the peripheral end of the wireare alternately deposited.

Furthermore, as shown in FIG. 8, a feeder 88 is formed at the bottomside of the bottommost dielectric thin film 80 such that it is connectedto the through hole 83.

The spiral wires 82, 84, 86 and 87 and the feeder 88 are formed at thedielectric thin films 80 by a printing technique or a photolithographytechnique commonly used in the semiconductor manufacturing process.

When the tester antenna 24 is formed with the above structure, it ispossible to make the tester antenna with a micrometer-scaled size suchthat it can be mounted on the substrate 21 having a size of severalmicrometers together with the IC chip 22.

A receiver antenna 32 is installed at the measurement controller 30 toreceive the signals from the tester antenna 24. The measurementcontroller 30 transforms the signals received at the receiver antenna32, and displays them by a monitor, or outputs them by a printer. Itstores the positional information of the measurement modules 20 as wellas the measured values.

The values measured at the tester antenna 24 and transmitted to themeasurement controller 30 are the phase and the amplitude of thefrequency signals from the source antenna 2.

A method of measuring the radiation characteristic of the source antenna2 using the above-structured antenna measurement system will beexplained with reference to FIGS. 1 to 13.

First, measurement modules 20 each with an IC chip 22 storing thepositional information intrinsic thereto and a tester antenna 24 aremounted at the predetermined locations of a tester body 10.

When the tester body 10 is made, it is placed at the predeterminedlocation (distant from the source antenna by 1 wavelength of thefrequency therefrom), and the source antenna 2 is operated.

With the operation of the source antenna 2, predetermined frequencysignals are generated, and transmitted in all directions. The testerantenna 24 of the measurement module 20 installed at the tester body 10receives the frequency signals (the electromagnetic waves) from thesource antenna 2, which partially generate induced power (using an RF-DCrectifier) to drive the IC chip 22.

The IC chip 22 uses the induced power from the tester antenna 24 withoutrequiring a separate power supply. Therefore, when a large-sized testerbody 10 is made, or even when a large number of measurement modules 20are mounted on the tester body 10, the wire for the power supplying isunneeded, and the structure is simplified while ensuring the easy makingthereof.

The IC chip 22 of the measurement module 20 samples the amplitude andthe phase of the frequency and the dimension of the induced power fromthe tester antenna 24, and stores and modulates them (using PSK and/orFSK modulation or CDMA). The IC chip 22 transmits the positionalinformation and the modulated signals via the tester antenna 24.

The measurement controller 30 receives the signals from the testerantenna 24 via the receiver antenna 32, and data-processes thepositional information and the modulated signals of the respectivemeasurement modules 20 to compute and store the data. The data areoutput by a display device or a printer.

The measurement controller 30 has a built-in software to transform themeasured values from the measurement modules 20 into the data of thefar-field range, and output them by a display device or a printer.

When the front of the source antenna 2 is measured and it is furtherintended to correctly measure the back lobe thereof, the measurement ismade once more while the source antenna 2 is rotated by 180°, or theinstallation position of the tester body 10 is varied by 180° to thatposition symmetrical thereto. Even in this case, as the measurement timeis extremely short, the time consumption is reduced significantlycompared to the conventional case.

FIG. 14 illustrates an antenna measurement system according to a secondembodiment of the present invention.

As shown in FIG. 14, the tester body 12 is shaped with a sphere, and themeasurement modules 20 are arranged on the inner surface of the testerbody 12 in a predetermined pattern.

It is preferable to store the number characteristic to the installationlocation of the respective measurement modules 20 at the IC chip 22using the coordination value (θ, φ) with the angle (θ) to the z axis andthe angle (φ) to the x axis.

In case the tester body 12 is formed with a spherical shape, it isbisected into upper and lower parts. With this structure, it is easy toinstall and replace the source antenna 2 within the tester body 12.

The source antenna 2 is fixed to a support 3 placed at the lower part ofthe tester body 12 such that it is positioned at the center of thespherical shaped structure. It is preferable to structure the sourceantenna 2 such that the height thereof can be varied in a controlledmanner.

Other structural components of the antenna measurement system accordingto the second embodiment of the present invention are the same as thoserelated to the first embodiment, and hence, detailed explanation thereofwill be omitted.

When the tester body 12 is formed with a spherical shape, it is possibleto correctly measure the all directional (360°) characteristic of thesource antenna 2 only with the one-timed measurement.

The measurement module 20 installed at the tester body 12 is structuredthat the tester antenna 24 is positioned perpendicular to the radius (r)of the tester body 12 being the measurement distance, thereby beinglocated vertical to the progressive direction of the electromagneticwave.

In order to obtain more correct far-field range data, the tester body 12is preferably structured such that the radius (r) thereof being thedistance from the source antenna 2 to the measurement module 20 becomesenlarged as much as possible.

FIG. 15 illustrates an antenna measurement system according to a thirdembodiment of the present invention.

As shown in FIG. 15, the tester body 14 is formed with a semi-sphericalshape, and the measurement modules 20 are arranged internal to thetester body 14 in a predetermined pattern.

The characteristic positional number of each measurement module 20 isinput into the IC chip 22 using the coordination value (θ, φ) with theangle (θ) to the z axis and the angle (φ) to the x axis.

The structure of the tester body 14 according to the third embodiment ofthe present invention is the same as the upper part of the tester body12 according to the second embodiment. In the case of the antennasinstalled on the ground, it is not needed to measure the characteristicthereof directed toward the ground, and hence, the structure accordingto the third embodiment is more effective than that according to thesecond embodiment.

Furthermore, when the tester body 14 is formed with a semi-sphericalshape, as shown in FIG. 16, it is possible that the tester body 14 is ina standing state as like with the structure related to the firstembodiment, and the measurement is made while the source antenna 2 isplaced on the extended line of the center of the tester body 14. In thiscase, it is like the structure in that the plane-shaped tester body 10according to the first embodiment is replaced by the semi-sphericalshaped tester body 14 according to the third embodiment.

FIG. 17 illustrates an antenna measurement system according to a fourthembodiment of the present invention.

As shown in FIG. 17, the tester body is shaped with a hexahedron, andthe measurement modules 20 are arranged at the inner surface of thetester body 16 in a predetermined pattern.

The characteristic positional number of each measurement module 20 isinput into the IC chip 22 using the three dimensional coordinationvalues (x, y, z).

With the hexahedron-shaped tester body 16, the manufacturing and theinstallation thereof can be easily made compared to the case where it isformed with the spherical shape.

The hexahedron-shaped tester body 16 is formed with a combinatorystructure where it is bisected into upper and lower parts, which arecombined with each other.

FIG. 18 illustrates an antenna measurement system according to a fifthembodiment of the present invention.

As shown in FIG. 18, the tester body 18 is shaped with a hexahedronwhere the bottom side is removed, and the measurement modules 20 arearranged internal to the tester body 18 in a predetermined pattern.

The structure of the tester body 18 according to the fifth embodiment isthe same as the upper part of the tester body 16 according to the fourthembodiment. In the case of the antennas installed on the ground, it isnot needed to measure the characteristic thereof directed toward theground, and hence, the structure according to the fifth embodiment ismore effective than that according to the fourth embodiment.

A method of measuring the radiation characteristic of the source antenna2 using the antenna measurement systems according to the second to thefifth embodiments will be now explained.

Measurement modules 20 each with an IC chip 22 storing thecharacteristic positional information and a tester antenna 24 arearranged at a tester body 10 in a predetermined pattern.

When the making of the tester body 10 is completed, the source antenna 2is operated while it is placed at the predetermined center locationwithin the tester body 10.

As described above, when the source antenna 2 is operated, frequencysignals are generated, and transmitted in all directions. The testerantenna 24 of the measurement module 20 internally placed on the testerbody 10 receives the frequency signals (the electromagnetic waves) fromthe source antenna 2. Detailed explanation for the subsequent operatingsteps will be omitted as they are the same as those related to the firstembodiment.

When the antenna characteristic of the source antenna 2 is measured inthe above way, the all-directional characteristic thereof can becorrectly known with the one-timed measurement. Furthermore, themeasurement is effectively made within the indoor space, and the totalinspection can be made at the antenna production site.

It is explained in relation to the second to fifth embodiments of thepresent invention that the tester body 12, 14, 16 or 8 is shaped with asphere, a semi-sphere, a hexahedron, or a hexahedron with no bottomside. Alternatively, it may be shaped with an octahedron, adodecahedron, an icosahedron, a cone, a quadrangular pyramid, or a horn.

It is further explained in relation to the first embodiment of thepresent invention that the tester body 10 is shaped with a plane.Alternatively, it may be shaped with a circular arc, a semicircle, acone, a quadrangular pyramid, or a horn.

With the inventive system and method for measuring the radiationcharacteristic of an antenna, the source antenna is operated, and at thesame time, the entire area of the tester body is measured. This makes itpossible to conduct the desired measurement in real time.

With the inventive system and method for measuring the radiationcharacteristic of an antenna, it is possible to make a very small-scaledtester antenna. Furthermore, it is also possible to precisely installmeasurement modules at the tester body per a very small distance (2-3μm). Consequently, the characteristic of the source antenna (the phase,and the intensity or amplitude of the frequency signal) can be simplyand correctly measured in real time. The measurement is made withoutmaking any error due to the variation in the weather or the temperature.

With the inventive system and method for measuring the radiationcharacteristic of an antenna, the total facility cost is significantlyreduced. Accordingly, it is possible to conduct measuring and testingthe antenna radiation characteristic in small-scaled factories orinstitutes.

Furthermore, with the inventive system and method for measuring theradiation characteristic of an antenna, with some installation space forthe plane-shaped or spherical-shaped tester body, it is possible tomeasure the characteristic of the source antenna. Therefore, it ispossible to make larger the volume of the tester body or to make thearrangement distance between the measurement modules very small. In thisway, it is possible to obtain more precise far-field range data.Particularly with the inventive system and method for measuring theradiation characteristic of an antenna, as it is possible to make thetester antenna in a very small scale, the impedance variation due to theinter-coupling of the neighboring antennas is extremely small even whenthe distance between the measurement modules is established to beseveral micrometers. Accordingly, even in such as case, the desiredprecise measurement values can be well obtained.

With the inventive system and method for measuring the radiationcharacteristic of an antenna, it is possible to measure the alldirectional antenna radiation characteristic within a very short periodof time. Consequently, not the sampling test but the total inspectioncan be made in the process of manufacturing antennas, thereby enhancingthe reliability of the resulting products significantly.

While the present invention has been described in detail with referenceto the preferred embodiments, those skilled in the art will appreciatethat various modifications and substitutions can be made thereto withoutdeparting from the spirit and scope of the present invention as setforth in the appended claims.

1. An antenna measurement system for measuring the radiationcharacteristic of a source antenna, the antenna measurement systemcomprising: a tester body placed apart from the source antenna with apredetermined distance; a plurality of measurement modules arranged atthe tester body in a predetermined pattern, each measurement modulehaving an IC chip for processing positional information and measuredvalues to generate relevant signals, and a tester antenna for receivingand transmitting the signals from the IC chip, and upon receipt offrequency signals from the source antenna, generating induced power fordriving the IC chip and transmitting the measured values for thefrequency signals to the IC chip; and a measurement controller forreceiving the signals from the tester antenna and processing thepositional information and the measured values of the respectivemeasurement modules.
 2. The antenna measurement system of claim 1wherein the tester body is shaped with a plane, a sphere, a semi-sphere,a hexahedron, or a hexahedron with no bottom side.
 3. The antennameasurement system of claim 1 or 2 wherein the measurement modules areinstalled at the locations of the tester body determined during theprocess of manufacturing the tester body.
 4. The antenna measurementsystem of claim 1 wherein the measurement module is made by mounting theIC chip and the tester antenna at a substrate shaped with a rectangle, acircle or an oval with a length or a maximum diameter of severalmicrometers.
 5. The antenna measurement system of claim 1 or 4 whereinthe tester antenna has wires spirally wound on two or more-leveledimagined planes, and the wires formed at the imagined plane neighborsare connected to each other at the central ends or peripheral endsthereof to form a single line.
 6. The antenna measurement system ofclaim 5 wherein a feeder is connected to the peripheral end or thecentral end of the wire formed at the bottommost imagined plane.
 7. Theantenna measurement system of claim 5 wherein the wire formed at theimagined plane is shaped with a rectangle, a circle, an oval, a hexagonor an octagon while being spirally wound forward or backward.
 8. Theantenna measurement system of claim 5 wherein an insulating layer isformed between the wires to prevent the possible short-circuiting. 9.The antenna measurement system of claim 1 or 4 wherein the testerantenna is structured such that spiral wires are formed on the one-sidedsurfaces of dielectric thin films, through holes are formed at therespective dielectric thin films such that the through holes arealternately connected to the central end or the peripheral end of therelevant wire, the dielectric thin films are deposited while filling thethrough holes with a conductive material, and a feeder is formed at thebottom side of the bottommost dielectric thin film such that the feederis connected to the through hole thereof.
 10. A method of measuring theradiation characteristic of a source antenna, the method comprising thesteps of: arranging a plurality of measurement modules at a tester bodyin a predetermined pattern, each module having an IC chip for processingpositional information and measured values to generate signals, and atester antenna for receiving and transmitting the signals from the ICchip, and upon receipt of frequency signals from the source antenna,generating induced power for driving the IC chip and transmitting themeasured values for the frequency signals to the IC chip; placing thetester body apart from the source antenna with a predetermined distancesuch that the tester body is perpendicular to the central axis of thesource antenna; and operating the source antenna, and operating themeasurement controller such that the measurement controller receives anddata-processes the positional information and the measured values fromthe tester antenna of each measurement module provided at the testerbody.
 11. A method of measuring the radiation characteristic of a sourceantenna, the method comprising the steps of: arranging a plurality ofmeasurement modules at a tester body in a predetermined pattern, eachmodule having an IC chip for processing positional information andmeasured values to generate signals, and a tester antenna for receivingand transmitting the signals from the IC chip, and upon receipt offrequency signals from the source antenna, generating induced power fordriving the IC chip and transmitting the measured values for thefrequency signals to the IC chip; placing the source antenna within thetester body such that the source antenna is positioned at the center ofthe tester body; and operating the source antenna, and operating themeasurement controller such that the measurement controller receives anddata-processes the positional information and the measured values fromthe tester antenna of each measurement module provided at the testerbody.
 12. The method of claim 11 wherein the tester body is shaped witha sphere, a semi-sphere, a hexahedron, or a hexahedron with no bottomside.